In 19 patients with idiopathic dilated cardiomyopathy and symptoms of congetive heart failure, left ventricular (LV) systolic performance and diastolic velocity profiles were assessed by two- dimensional echocardiogra...In 19 patients with idiopathic dilated cardiomyopathy and symptoms of congetive heart failure, left ventricular (LV) systolic performance and diastolic velocity profiles were assessed by two- dimensional echocardiography and pulsed wave Doppler at rest and during handgrip exercise before and ninety minutes after administration of captopril (mean dose 25 +12mg; range 12. 5─50mg). Although heart rate and blood pressure increased similarly during handgrip exercise before and after captopril treatment, both were lower with handgrip exercise during captopril treatment. The results from this study indicated that acute angiotensin converting enzyme inhibition with captopril reduces preload and afterload and ameliorates handgrip exercise-induced LV systolic and diastolic filling dysfunction in patients with congestive heart failure secondary to idiopathic dilated cardiomyopathy.展开更多
Photoplethysmogram(PPG)is a noninvasive method for detecting human cardiovascular pulse wave using optical technology.The PPG containing a lot of physiological information is from the MIMIC database.This paper propose...Photoplethysmogram(PPG)is a noninvasive method for detecting human cardiovascular pulse wave using optical technology.The PPG containing a lot of physiological information is from the MIMIC database.This paper proposes a combinatorial method of ensemble empirical mode decomposition(EEMD),cepstrum,fast Fourier transform(FFT)and zero-crossing detection to improve the robustness of the estimation of pulse rate(PR),heart rate(HR)and respiratory rate(RR)from the PPG.First,the PPG signal was decomposed into finite intrinsic mode functions(IMF)by EEMD.Because of its adaptive filtering property,the different signals were reconstructed using different IMFs when estimating different physiological parameters.Second,the PR was obtained by zero-crossing detection after rejecting low frequency IMFs containing artifacts.Third,IMFs with frequency between 1.00 Hz to 1.67 Hz(60 beats/min to 100 beats/min)were selected for estimating HR.Then,the frequency band that reflects the heart activity was analyzed by the cepstrum method.Finally,the respiratory signal can be extracted from PPG signal by IMFs with frequency between 0.05 Hz to 0.75 Hz(3 breahts/min to 45 breaths/min).Then the spectrum of signal was obtained by FFT analysis and the RR was estimated by detecting the maximum frequency peak.The algorithm has been tested on MIMIC database obtained from 53 adults.The experiment results show that the physiological parameters extracted by this integrated signal processing method are consistent with the real physiological parameters.And the computation load of this method is small and the precision is high(not larger than 1.17%in error).展开更多
Objective： Comparison of global end-diastolic volume index （GEDVI） obtained by femoral and jugular transpulmonary thermodilution （TPTD） indicator injections using the EV1000NolumnView device （Edwards Lifesci- e...Objective： Comparison of global end-diastolic volume index （GEDVI） obtained by femoral and jugular transpulmonary thermodilution （TPTD） indicator injections using the EV1000NolumnView device （Edwards Lifesci- ences, Irvine, USA）. Methods： In an 87-year-old woman with hypovolemic shock and equipped with both jugular and femoral vein access and monitored with the EV1000NolumeView device, we recorded 10 datasets, each comprising duplicate TPTD via femoral access and duplicate TPTD （20 ml cold saline） via jugular access. Results： Mean femoral GEDVI （（674.6±52.3） ml/m2） was significantly higher than jugular GEDVI （（552.3±69.7） ml/m2）, with P=-0.003. Bland-Airman analysis demonstrated a bias of （＋122±61） ml/m2, limits of agreement of -16 and ＋260 ml/m2, and a percentage error of 22%. Use of the correction-formula recently suggested for the PiCCO device significantly reduced bias and percentage error. Similarly, mean values of parameters derived from GEDVI such as pulmonary vascular permeability index （PVPI; 1.244±0.101 vs. 1.522±0.139; P〈0.001） and global ejection fraction （GEF; （24.7±1.6）% vs. （28.1±1.8）%; P〈0.001） were significantly different in the case of femoral compared to jugular indicator injection. Fur- thermore, the mean cardiac index derived from femoral indicator injection （（4.50±0.36） L/（min.m2）） was significantly higher （P=0.02） than that derived from jugular indicator injection （（4.12±0.44） L/（min.m2））, resulting in a bias of （＋0.38±0.37） L/（min.m2） and a percentage error of 19.4%. Conclusions： Femoral access for indicator injection results in markedly altered values provided by the EV1000NolumeView , particularly for GEDVI, PVPI, and GEF.展开更多
文摘In 19 patients with idiopathic dilated cardiomyopathy and symptoms of congetive heart failure, left ventricular (LV) systolic performance and diastolic velocity profiles were assessed by two- dimensional echocardiography and pulsed wave Doppler at rest and during handgrip exercise before and ninety minutes after administration of captopril (mean dose 25 +12mg; range 12. 5─50mg). Although heart rate and blood pressure increased similarly during handgrip exercise before and after captopril treatment, both were lower with handgrip exercise during captopril treatment. The results from this study indicated that acute angiotensin converting enzyme inhibition with captopril reduces preload and afterload and ameliorates handgrip exercise-induced LV systolic and diastolic filling dysfunction in patients with congestive heart failure secondary to idiopathic dilated cardiomyopathy.
文摘Photoplethysmogram(PPG)is a noninvasive method for detecting human cardiovascular pulse wave using optical technology.The PPG containing a lot of physiological information is from the MIMIC database.This paper proposes a combinatorial method of ensemble empirical mode decomposition(EEMD),cepstrum,fast Fourier transform(FFT)and zero-crossing detection to improve the robustness of the estimation of pulse rate(PR),heart rate(HR)and respiratory rate(RR)from the PPG.First,the PPG signal was decomposed into finite intrinsic mode functions(IMF)by EEMD.Because of its adaptive filtering property,the different signals were reconstructed using different IMFs when estimating different physiological parameters.Second,the PR was obtained by zero-crossing detection after rejecting low frequency IMFs containing artifacts.Third,IMFs with frequency between 1.00 Hz to 1.67 Hz(60 beats/min to 100 beats/min)were selected for estimating HR.Then,the frequency band that reflects the heart activity was analyzed by the cepstrum method.Finally,the respiratory signal can be extracted from PPG signal by IMFs with frequency between 0.05 Hz to 0.75 Hz(3 breahts/min to 45 breaths/min).Then the spectrum of signal was obtained by FFT analysis and the RR was estimated by detecting the maximum frequency peak.The algorithm has been tested on MIMIC database obtained from 53 adults.The experiment results show that the physiological parameters extracted by this integrated signal processing method are consistent with the real physiological parameters.And the computation load of this method is small and the precision is high(not larger than 1.17%in error).
文摘Objective： Comparison of global end-diastolic volume index （GEDVI） obtained by femoral and jugular transpulmonary thermodilution （TPTD） indicator injections using the EV1000NolumnView device （Edwards Lifesci- ences, Irvine, USA）. Methods： In an 87-year-old woman with hypovolemic shock and equipped with both jugular and femoral vein access and monitored with the EV1000NolumeView device, we recorded 10 datasets, each comprising duplicate TPTD via femoral access and duplicate TPTD （20 ml cold saline） via jugular access. Results： Mean femoral GEDVI （（674.6±52.3） ml/m2） was significantly higher than jugular GEDVI （（552.3±69.7） ml/m2）, with P=-0.003. Bland-Airman analysis demonstrated a bias of （＋122±61） ml/m2, limits of agreement of -16 and ＋260 ml/m2, and a percentage error of 22%. Use of the correction-formula recently suggested for the PiCCO device significantly reduced bias and percentage error. Similarly, mean values of parameters derived from GEDVI such as pulmonary vascular permeability index （PVPI; 1.244±0.101 vs. 1.522±0.139; P〈0.001） and global ejection fraction （GEF; （24.7±1.6）% vs. （28.1±1.8）%; P〈0.001） were significantly different in the case of femoral compared to jugular indicator injection. Fur- thermore, the mean cardiac index derived from femoral indicator injection （（4.50±0.36） L/（min.m2）） was significantly higher （P=0.02） than that derived from jugular indicator injection （（4.12±0.44） L/（min.m2））, resulting in a bias of （＋0.38±0.37） L/（min.m2） and a percentage error of 19.4%. Conclusions： Femoral access for indicator injection results in markedly altered values provided by the EV1000NolumeView , particularly for GEDVI, PVPI, and GEF.
